A serious problem confronting tank barge operators transporting digested sewage sludge, is the removal of residue comprising sludge solids which settle out of suspension during transit. This residue, which is normally too thick to flow quickly, can reduce barge capacity substantially. In order to remove this residue, it is necessary to forcefully dilute the solids with a water jet which has the effect of breaking up and flowing agglomerated heavy residue material.
Manning a high pressure water hose to remove the residue is costly and hazardous to labor, and while tank cleaning machines heretofore available have been tried, their slow progression to all tank surfaces involved has not been conducive to agitating the residue body. Furthermore, substantial time and wash water is wasted cleaning the tank top and sides where residue is not an initiating problem.
The residue, which is normally too thick to flow readily, can reduce barge capacity substantially and can accummulate and require major labor clean up efforts if not quickly removed each trip. Sending a man into a barge tank with a high-pressure water hose just to clean up residue at any time is costly and unduly hazardous, under most conditions, just to maintain economical cargo capacity.